Refurbished Grade B is the second-best quality you can expect from a refurbished device. Refurbished Grade B products feature some light scratches or scuffs. Bear in mind this is only a cosmetic condition difference with Grade A devices; Grade B laptops and phones are tested thoroughly and are perfectly functional.
Because of these small signs of use, Grade B products are more affordable than refurbished Grade A devices. Something to keep in mind if your budget is restricted.
Refurbished Grade C is the lowest quality of a refurbished phone or laptop that is still in working order. Although refurbished Grade C devices have been tested and are confirmed to work, they do show signs of heavy or even excessive usage by their previous owner.
You will see very noticeable cosmetic issues with a refurbished Grade C device including more significant scratches and signs of wear and tear on the case or lid. Grade C devices are cheaper than Grade A and Grade B products, making them ideal for those who need a new phone or laptop but have very little money to spare.